Ammonia apparatus.



PATENTED MAR. 31, 1908. J. ROBSON.

AMMONIA APPARATUS.

\ APPLICATION TILED KAY 3. 1907.

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No. 883,487. 7 P-ATENTED MAR. 31, 1908.

* J. ROBSON.

AMMONIA APPARATUS.

APPLICATION FILED KAYs. 1907.

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h/l'hzerres No.883,487. I PATENTED MAR-31, 1908.

J. ROBSON.

' AMMONIA APPARATUS.

APPLICATION FILED HAYS, 1907.

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No. 883,487. PATENTED MAR. 31, 1908. I

J ROBSON. AMMONIA APPARATUS.

APPLICATION FILED MAY3, 1907.

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AMMONIIA APPARATUS.

APPLICATION nun MAYa. 1901. V

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PATENTED MAR. 31, 1908.

J, ROBSON; AMMONIA APPARATUS.

APPLICATION FILED KAY 3. 1907.

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APPLICATION PILED'MAY 3. 1907.

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UNITED STATES JOHN ROBSON, OF

WALLSEND, ENGLAND, ASSIGNOR TO CLARKE CHAPMAN & COMPANY LIMITED, OF DURHAM, ENGLAND.

AMMONIA APPARATUS.

Specification of Letters Patent. Application filed May 3, 1607.

Patented March 31, 1908. Serial No. 371,651;

ject of the King of England, residing at Wallsend, N orthumberland, England, have invented a certain new and useful Ammonia Apparatus, of which the following is a specification.

This invention relates to improvements in ammonia apparatus specially ada ted for the propulsion of submarine vessels, ut can be used to advantage for pro elling other vessels and consists substantial y in the combinations of parts and constructions hereinafter described and more specifically pointed out in the claims.

Referring to the accompanyingdrawings, Figures 1, 2 and 3 are separate sectional elevations showing together the entire plant. and 6 are plan views'of Figs. 1, 2 and 3 respectively. Fig. 7 is a cross section on line A-A of Fig. 1 and Fig. 8 is a similar view on line B B of Figs. 9 to 11 show details of construction of the ammonia tion through the ammonia cylinder, Fig. 10 a similar section through the oil cylinder and Fig. 11 a plan view of top of the oil cylinder, with the space casting between the two cyl inders removed. I

In said dray'ings 1 indicates the shell or skin of a submarine vessel and 2 the propeller shafts therefor.

The apparatus comprises oil motors 3 of the known type for propelling submarine vessels, having applied thereto however ammonia cylinders 4, 5 which may be of the tandem type, having their piston rods connected to the trunks of the oil motors. The space or spaces 6 between the cylinders may be inclosed and communicate by a pipe with the absorbers as hereinafter described for the purpose of absorbing any gas which may accumulate therein.

8 designates the exhaust from the oil 1notors.

Adjacent the motors is located the am monia generator comprising a cylindrical vessel 7 inclosing a number of small steel tubes 16 expanded into tube plates 18 and 19 therein, and the heat from the water jacket and exhaust 8 of the oil motor may be used for producing pressure... in said generator, for which purpose the latter is provided with a chamber 11 having an outer circle of tubes 12, and into the chamber 11 the exhaust motor cylinders 4 and '5 and pipes and having imparted its heat to the liquid in said generator is exhausted at the lower end thereof through the pipe 153 Figs. .1 and 7. 14 indicates a tube plate through which the tubes 12 pass.

The u per part 9 of the generator is provided with a number of bafiies 10 forming a Water separator, the spaces between such baflies communicating through holes 13 with the outer circle of tubes 12 which pass through the above mentioned exhaust chamber 11, said tubes12 projecting beyond the top tube plate 14 for a certain distance to allow water to accumulate and seal said holes, the arrangement being such that when the water reaches the top of said tubes it will pass into the lower chamber 15 of the generator to mix With the general solution. The gas given off from the ammonia and water solution in the body 7 of the generator passes oif through a central pipe at the upper part thereof and branch pipes 21 and 22 to the ammonia cylinders 4 before mentioned. Stop valves 23 are provided between the'pipes 21 and 22, and 24 represents a further branch pipe between the pipes 21 and 20.

25 indicates exhaust chambers for the the exhaust therefrom passes through the pipe 26 havin bottom of the first absorber 27 being split up by a spreader bsorber is preferably of the type described in the specification of in previous Letters Patent N 0. 344087, filed 19- November 1906, being provided at its lower part with a vertical perforated plate 30 and with a number of horizontal baflie plates 31, 33 and 35 provided with openings 32, 34 and 36 respectively, at alternate opposite ends as shown in Fig. 2 the exhaust gas passing through said vertical perforated plate and the apertures in the horizontal plates being thus caused to travel from side to side of the absorber till it reaches the top where, should any gas remain unabsorbed, it passes off by pipes 37 and 168,the latter having a non-return valve 151, into and through a perforated pipe or rose 39 at the bottom of the second absorber 38 then rises upwards through a perforated plate 152 therein to the finally passing off by a pipe 40 to a chamber 41, at the top of the third or last absorber 42,. where it is met by a jet of cold weak ammonia solution sprayed into said from the oil motors enters through a pipe or chamber 41 through a pipe 44 and nozzle 43. By this means all the gas will become absorbed and the liquid will settle in this last absorber 42.

The absorbers 27, 38 and 42 are provided with refrigerating coils 45 supplied with anhydrous ammonia from a suitable receiver and the ammonia evaporated in said coils Several other receivers 50, 51, 52 and 53.

are provided for the storage of anhydrous ammonia for propulsion of the vessel when the latter is below the surface of the water and the supply from one or more of these receivers may be used for cooling the absorbers as above mentioned. The con- 1 nections are as follows: 54 indicate pipes leading from the storage tank 53 to a receiving pipe 55 and 56 pipes from the latter to the coil supply pipe 57, stop valves 58 being provided in said pipes 56. -When all the anhydrous ammonia has been evaporated from the receivers and the vessel is again brought to the surface they may be recharged by liquefying the ammonia produced in the generator 7 by passing it into liqueiiers or condensers 59 and 60 from which it passes into each of the receivers, the communication being controlled by suitable valves or the like. For this purpose the connections may be arranged as follows: 61 is a stop valve next the aforesaid branchpipe 24 and 62 a pipe between said valve and the liquefier 59. 63 is a second stop valve next pipe 24 and 64 a pipe leading therefrom to the liquelier 60. 65 designates a branch pipe, and 66 and 67 are stop valves in pipes 68 and 69 respectively leading from the bottom of the liquefiers 59 and 60 respectively to said branch pipe 65 which is in communication with the receiver 50 by means of pipes 70 and 71, stop valve 72, pipe 73 and branches 74. The branch pipe 65 is also in communication with the receiver 51 through pipes'70 and 75, stop-valve 76 pipe 77 and branches 78, with the receiver 52 through stop-valve 79 pipe 80 and branches 81, and with the receiver 53 through pipe 82, stop-valve 83, pipe 55 and branches 54. The liquefiers contain tubes 144 let into tube plates 143 as shown in Fig. 7.

A pump is provided and arranged so that it can suck the ammonia from any of the receivers and deliver it to evaporating coils, so located as to be surrounded by the seawater which passes into a semi annular space in the vessel through a small aperture preferably near the bow end. The flow of let when required.

'nia cylinders 4 and water is regulated through an outlet at the stern, a suitable arrangement of valves being also provided for closing both inlet and out- The evaporating coils are so arranged as drawal for examination and repairs. The said pump is mounted on a bec plate and standard 84 and the cylinder 85. thereof works the two barrels 86 and 87 and a measuring valve 88. The barrel 86 sucks the ammonia from any of the receivers through the aforesaid branch pipes 65 stop valve 89 and pipe 90 and delivers through the stop-valve 91 and pipe 92 into pipe 93 through branches 94' into the evaporating coils 95; and from pipe 93 through pipe 96 into pipe 97 through branches 98 into other evaporating coils 99.

The gas produced by the evaporation in the coils 95 and 99 is conveyed to the ammoafter doing work therein is exhausted into the first absorber 27 for instance in the following manner. The gas evaporated in the coils 95 is delivered through branches 94 into the pipe 93 and thence by pipes 100 into other pipes 101 to a tube 102. The gas evaporated in the other coils 99 is delivered through branches 98 into pipe 97 and thence by gipes 103 connecting the pipes 101. The sail tube 102 is in communicationwith a pipe 104 which conveys the gas to the ammonia cylinders 4. A stop valve 105 is provided in the pipe 104. The gas exhausts from cylinders 4 through chamber 25 and pipe 26 into absorber 27.

The pump when not in use for supplying the evaporating coils as described, that is to say, when the boat has risen to the surface, is used for sucking strong ammonia solution from the first absorber 27 and conveying it into a heat interchanger. 110 adjacent to the pump, from which interchanger it passes through a non-return valve to the water jackets of the oil motors and absorbing heat therein passes through a pipe and non-return valve to the generator. This may be effected as follows, viz: through pipe 106 leading from the absorber to a vertical pipe 107 which is a continuation of the pipe 70 be fore referred to, a stop-valve 108 being pro-' vided in pipe 106. 109 indicates a pipe leading from the pump barrel 86 to the bottom of the heat interchanger and provided with a stop valve 111. 112 designates the non-return valve at the upper part of the heat in terchanger 110 and 113 the pipe leading therefrom to the water-jackets of the oil motors 3. Pipes 114 provided with non-return valve 115 lead from said water jackets to the generator 7. Simultaneously with the above operations the corresponding or proportional quantity of weak ammonia solution is discharging from the bottom of the generator 7 by a pipe 116 having a regulating valve 117 through the measuring valve 88 which is to be capable of withent No. 344087 ab .142 the discharge preferably of the construction described in the specification of my previous Letters Pat: ove mentioned, from which valve it enters the heat-interchanger 11.0 by a pipe 118 communicating with the casing thereof surrounding the containin from the first absorber 27. from the generator 7 after b passes out tube 47 containing the gas evaporated from the refrigerating coils 45 of the absorbers, as previously explained. The solution is thus cooled and. ultimately delivered by the nozzle 43 in the form of spray to the chamber 41 in communication with the last absorber. The strong solution pum ed from the first absorber is replaced tion is delivered by a pipe 124 into the bottom of the first absorber. For this purpose the following connections etc. may be made. 121 is a suction pipe leading from the abto the pump-barrel 87, and

42 respectively. 124 designates the delivery ipe from pum arrel 87 to the bottom of absorber 27 an 125 a stop-valve in said pipe 124. The latter is connected to the pipe 44 before referred to by a pipe 126 provided with a stop valve 127, and the bottom of the absorber 38 is connected to top of absorber 42 by means of a pipe 128. The pump is so constructed or arranged that the quantity pumped can be reduced or increased perated to quantity not required in the firstabsorber into the second absorber. This by means of tappet valve gear, the tap ets being adjusted to open and close the va ves according to the quantity required.

The condensers 59, 60 above mentioned are each provided with a separate circulating pump 135, 136 respectively, the delivery pipes of which are connected to the bottom of the condenser casings, and the discharge pipes from the latter to the top of said casso that the water circulates round 137 and 138 indicate the suction pipes to the circulating pumps 135 and 136; 139 is the delivery pipe from pump 135 to the bottom of tube chamber of condenser 59; 140 the discharge pipe from the top of the latter; 141 the delivery pipe from pump 136 to the bottom of tube chamber of condenser 60, and

pipe from the. top of said Tl condenser 60. 1e following connections j stop-valve 132 connects receiver 51 to pipes the receiver 52 to said pipe 37.

This

stop valve 134 connects 145 indipressure pipe from pipe 48 to pump cylinder 85 (Fig. 1)and having a stop valve 146; 147 is the exhaust pipe with non-return valve 148 from cylinder 85 to bottom of absorber 27. 149 a pipe connecting vertical pipe 107 to pipe 37 leading to first absorber and 150 a stop valve in said pipe 149.

Referring to Figs. 9, 10 and 11 the cylinders of the oil motor and the ammonia cylinders are shown in combination. 4 indicates the ammonia cylinder and 3 the cylinder of the oil motor. The ammonia cylinder 37 and pipe 133 with 'has double stufiing boxes 154, with a distance piece 155 located between them into which oil is forced under pressure. The space 6 between the twocylinders is closed by suitable doors and a pipe communicating with the ammonia absorber is connected to the said space.

157 indicates a stuffing box for the oil motor cylinder. The piston rod 158 is hollow and a tube 159 enters said rod to a suitable clearance distance from the bottom thereof when the engine is at the upper dead center. By means of a suitable cam arrangement an injection of anhydrous ammonia takes place at every top stroke. The said ammonia is instantly flashed into vapor owing to the heat of the piston rod, producing the necessary cooling effect to said piston rod and producing power or doing work above the ammonia piston 156.

160 is the cooling jacket for the cylinder 3 which in this of said jacket. rounding the jacket 160 and spectively are filled with a suitable non-conducting material such as asbestos.

The oil motor stufling box 157 is surrounded by ammonia solution in the space 163 shown also in dotted lines in Fig. 11.

167 shows a method of packing the studs with nut and washer. packing may be inserted in the stufling box.

165 indicates the piston in cylinder 3 and 166 is connecting rod.

The action or cycle of operations of the apparatus is as follows: Before starting the apparatus the first absorber 27 must be about half filled with water and the second and third absorbers 38 and 42 should be about three quarters full; the receivers 50 51 52 and 53 must be charged with anhydrous ammonia, the generator 7 should be charged up to the required level with amthereof to overflow into receiver 50 a valve .125 on the delivery pipe-124 which enters the absorber 27 near the bottom must be opened to allow a portion of the weak solution'passing from'the absorber 42 which 70 forms the jet 43 to enter the bottom of absorber 27. When'the anhydrous ammonia in receiver 51 becomes exhausted the receiver 52 may be turned on and when 50- is filled with the ammonia solution the-valve 75 132 can be opened whereupon the receiver 5 1 will receive the overflow from 27 aft'erwhich the valve 134 must be opened and the receiver 52 filled with the strong ammonia solution. The absorbers 38 and 42 will then go be charged, afterwhich' the receiver 53-will be emptied, the whole of the ammonia will become absorbed in the water, and the boat must now come to the surface. The temperature of the exhaust'ammonia vapor on 85 entering the absorbers will be at least 10 F. below zero yet the latent heat of the gas wouldsoon cause the absorbers to become too'hot, therefore the anhydrous ammonia is passed from the receiver 53 into the ab- 90 sorber coils'45 where it takes up its heat of vaporization from the solution in the ab sorbers, whereupon the gas is passed to the cylinders 5 where it is expanded and does work thus cooling the absorbers. 5 The next cycle of operations to be described is that which is adopted when the boat is upon the surface of the water. The oil motors can be run as internal-combustion engines directly coupled to the propeller 100 shafts and can be started or reversed by the ammonia cylinders, suificient anhydrous ammonia still remaining in the evaporating coils'95 and 99 toallow a considerable number of maneuvers to be executed when work- 5 ing in combination with the oil motors on first coming to the surface. The reversing gear on the ammonia cylinders can with the same movement also reverse the camswhich actuate the-valves of the oil motors. The

oil motors must be run for a short time to enable the exhaust gases to heat upthe generator 7. The exhaust passes from the oil motors by the pipes 8 to the chamber 11 of 50 communicates with the cylinders 50, 51, 52 the generator, then passes through the tubes 115 and 53 and the delivery to pipe 93 which to the bottom and after imparting its heat to supplies the coils 95 and 99. When the conthe strong ammonia solution contained in tents of receiver 50 has been evaporated the the 'body of the generator the remaining solution in absorber 27 will be completely gases will pass out by the pipe 153 to the at- 55 saturated and the excess vapor having bemosphere from any convenient part of the 120 comeabsorbed in the absorbers 38 and 42 boat. The pump barrel 86 may draw the the solution will also have increased in bulk strong ammonia solution from any of the renearly to the top of 27 The valve 130 must i ceivers O 51 and 52 or from the absorber 27 now be opened to allow the strong ammonia by the pipe 90 and passing it through the 60 solution to overflow from the top of 27 into heat interchanger 110 then to the jackets of 125 the empty receiver 50 and at the same time he oil motorsv by the pipes 113 and after the suction of the feed pump for the coils 95 having taken up the heat from the jackets it and 99 is opened to the receiver 51. is passed out by the pipes 114 to the non- To enable the absorber 27 to absorb more return valve 115 and finally into the genera- 65 vapor and also the strong solution at the top tor. At the same time a regulated quantity 130 monia and water in about equal proportions, and the evaporating coils 95 and 99 should be also charged with anhydrous ammonia.

'If the temperature of the sea-water be say 50 Fahrenheit a pressure of 74 pounds per square inch above atmosphere will be raised and fill the horizontal ammonia vapor receiver or tube 102, this pressure is due to the evaporation of the anhydrous ammonia in the coils'95 and 99 and the vapor is conveyed from tube 102 through the. pipes 104 to the ammonia cylinders 4 of the oil motors 3, the adjacent cylinders 5 being at the same time open to communication with the op 15 posite horizontal ammonia vapor receiver or tube 47 which communicates by the pipes 46 with the coils 45 in the absorbers 27 38 and 42. Thesecoils are supplied through the pipes 56 and 57 with anhydrous ammonia from the receiver 53. The valves for admitting the ammonia vapor to the cylinders 4 and 5 should both be operated by the same lever or other mechanical appliance which may be used for starting and stopping the motors.

' The cycle to be now described is that which would be adopted when the boat is submerged. The ammonia vapor under pressure, coming from the two sources above mentioncd is admitted by the same valve lever to the cylinders 4 and 5, which work similarly to a double-acting steam engine and drive the propeller shafts 2, the exhaust ammonia vapor being passed away by the pipes 26 and through the non-return valve 28 into the absorber 27. Any vapor not absorbed in 27 is passed out by the pipe 37 and spread by the rose pipe 39 at the bottom of the absorber 38 and should any vapor now remain 40 unabsorbed it will pass out by the pipe 40 into the chamber 41 meeting at the entrance a jet of cold weak solution which is drawn by the pump barrel 86 from the bottom of the absorber 42 and delivered into the pipe 44 45 to form the jet at 43 which will absorb the whole of the vapor inabsorber 42.

The feed of anhydrous ammonia to the evaporating coils and 99 is maintained by the pump barrel 86 the suction of which of weak ammonia solution is passed out at the bottom of the generator by the pipe 116, through the measuring valve 88into the easing of the heat interchanger and leaving the casing at the top by the pipe 119 passes out by the nozzle 43 in the chamber 41'of the absorber 42. When working on the surface with the generator 7 the nozzle43 is always F. 77 F. ssuming that the oil motors have run long enough to raise a pressure in the generator say of 160 lbs. the valves 61 and 63 Fig. 7 should be opened to aflord commuare cooled by the circulating pumps 135, 136 passing the water through the casings, the ammonia gas being thus liquefied within the tubes. he ammonia vapor is now confined between the generator and condensers and if the rapid charging of the receivers with anydrous ammonia is desired, the boat must be run with the oil motors only. The first receiver to be recharged with anhydrous ammonia should be 53 then 52 and then 51. When the cylinders have all been emptied of the anhydrous ammonia it becomes necessary, when recharging, to first feed the generator with some of the strong solution from the absorbers to afford room for the weak solution passing from the generator to the jet nozzle 43. In practice the boat may not hours but when frequently coming to the surface the receivers 51 52 and 53 should, as far as possible, be first refilled with anhydrous ammonia, after which the ammonia solution in receiver 50 can be used in the gen erator and the vapor passed out by the pipe 20 and by the pipes 21 to the ammonia cylinders 4. The motors 3 may now be worked as internal combustion and motors in combination, the pump barrel 87 draws the solution from the absorber 38 by the pipe 121 near the top and delivers it by the pipe 124 Figs.

. and 5 into the absorber 27 to compensate he weak solution discharged from the bottom of the generator.

wish it to be understood that I do not 'limit myself to the exact construction and arrangement of the apparatus above de scribed since the same may be varied within 1 certain limits without departing from the spirit of the invention.

What I claim as my invention and desire to secure by Letters Patent of the United tates is :5

age of and supply of ammonia to the ammonia motor and means operatable by the Oll motor for regenerating the ammonia supply,

generator.

3. T an Oll motor and an member, generator comprising a main' chamber, a series of tubes therein, an intermediate chamber in communication with the exhaust of the oil motor, a series of tubes in said intermediate chamber, a water separator above said intermediate chamber, and a series of afHes in said separator, the latter being in communication with the main chamber through the aforesaid series of tubes in the intermediate chamber; means for supplying ammonia from the generator to the ammonia motor, a series of interconnected absorbers,

a driven member, an 011 motor, and

an ammonia motor connected to be severally and orization successively to collectively operative on said driven member, an ammonia generator, means for passing exhaust gases from the oil engine through the generator, means for supplying ammonia from the generator to the ammonia motor, a series of interconnected absorbers, refrigerating coils therein, an auxiliary anhydrous ammonia receiver in communication with said refrigerating coils, means for passing products of evaporation in said coils to the ammonia motor, means for passing the gaseous exhaust from the ammonia motor to the first of said absorbers and means for returning ammonia solution from the latter back to the generator.

6. The combination of a driven member, an oil motor and an ammonia motor connected to be severally and collectively oper ative on said drivenmember, a plurality o anhydrous ammonia receivers means for supplying the contents of said receivers after vapthe ammonia motor, an absorber, means for passing the gaseous exhaust from the ammonia motor to said absorber, and means for passing overflow from the absorber back to emptied re ceivers.

7. The combination of a driven member, an oil motor, and an ammonia motor connected to be severally and collectively operative on said driven member, an ammonia generator, means for passing exhaust gases from the oil engine through the generator, a plurality of anhydrous ammonia receivers, evaporating coils in communication therewith, means for in said coils to the ammonia motor, an ab sorber, means for passing the gaseous exhaust from the ammonia motor to said absorber, means for recharging emptied receivers with liquefied ammonia from the generator.

8. The combination of a driven member, an oil motor havin a water jacket and an ammonia motor connected to be severally and collectively operative on said driven an ammonia generator, means for member,

passing exhaust gases from the oil engine through the generator a plurality of anhy drous ammonia receivers adapted to be successively placed in ammonia motor, evaporating coils in com" munication with said receivers, means for passing vapor produced in said coils to the ammonia motor, a plurality of absorbers connected in series, absorbers, means ating coils with anhydrous ammon receiver aforesaid, means for passing gaseous exhaust from the ammonia motor of said absorbers, means in the last absorber for completely absorbing for supplying said refrigermeans for from the 1 jacket back to the generator,

passing the vapor produced communication with the refrigerating coils in said a from a to the first gaseous exhaust arrlvmg therein from a preceding absorber, a passing strong first absorber removed fronr tliroi'igh the heat interchanger and oil motor a measuring valve and means for passing weak ammonia solution from the generator through said measuring valve and the heat interchanger to the aforesaid absorbing means in the last absorber.

9. The combination of a driven member, an oil motor having a water jacket and an ammonia motor connected to be severally and collectively operative on said driven member, an ammonia generator, means for passing exhaust gases from the oil enginethrough the generator a plurality of anhydrous ammonia receivers adapted to be successively placed in communication with the ammonia motor, evaporating coils in communication with said receivers, means for passing vapor produced in said coils to the ammonia motor, a plurality of absorbers connected in series, refrigerating coils in said absorbers, means for supplying said refrigerating coils with an hydrous ammonia from a receiver aforesaid, means for passing gaseous exhaust from the ammonia motor to the first of said absorbers means for passing overflow of ammonia solution from said first absorber to emptied receivers, means in the last absorber for com plet'ely absorbing gaseous exhaust arriving therein from a preceding absorber, a heat interchanger means for passing strong ammonia solution from-the first absorber through the heat interch'anger back to the generator, a measuring valve, means for passing weak ammonia solution from the generator through said measuring valve and the heat interohanger to the aforesaid absorbing means in the last absorber and means for recharging emptied receivers with liquefied ammonia from the generator.

10. The combination of a driven member an oil motor, and an ammonia motor adapted to be severally and collectively operative on said driven member, an ammonia generator, means for passing exhaust gases from the oil engine through the generator, a plurality of anhydrous ammonia receivers, evaporating coils in communication with said receivers means for passing vapor produced in said coils to the ammonia motor, a plurality of absorbers connected in series, refrigerating coils in said receivers in communication with an anhydrous ammonia receiver aforesaid, means for passing vapor produced in said refrigerating coils to the ammonia motor, means for passing gaseous exhaust from the ammonia motor to the first of said absorbers, means for passing overflowof ammonia therefrom to emptied receivers, an ammonia spray in the last of said absorbers, a heat interchanger, means for passing strong ammonia solution from the first absorber through the heat interchanger back to the generator, means for replacing the ammonia solution the first absorber by other and oil motor jacket the anhydrous ammonia fication in the presence of two Ireccivers, evaporating coils in communication therewith, adapted to be surrounded b the water of flotation; means for passing the I have slgned this speci- 2 witnesses.

11. The combination with a navigable "1 vessel of a propelling member, an oil motor, JOHN ROBDON' and an ammonia motor connected to be sever- Witnesses: ally and collectively operative on said driven J. A. DIXON,

member, a plurality of anhydrous ammonia Anon. ROXBURGH. 

